Homeland Defense operations help ensure the integrity and security of the Homeland by detecting, deterring, preventing, or, if necessary, defeating threats and aggression against the United States as early and as far from its borders as possible so as to minimize their effects on US society and interests. [Civil Support addresses those DoD actions] to assist civilian authorities in order to safe lives, protect property, enhance public health and safety, or to lessen or avert the threat of a catastrophe. (Homeland Defense and Civil Support Joint Operating Concept, 2007)

Homeland Defense/Civil Support covers a very broad range of topics and responsibilities. While WMD terrorism has a very low probability of occurrence as compared to conventional terrorism, the consequences mandate a focused and coordinated Federal response. With DoD, installation commanders are responsible to protect individuals on U.S. military installations and facilities from attacks or incidents that may include CBRN threats. In addition, the U.S. military must protect its power projection capabilities within the United States to ensure its ability to engage overseas adversaries. Under the mission of Defense Support of Civil Authorities, the U.S. military supports the Federal response to domestic CBRN incidents under a broad CBRN Response Enterprise, composed of National Guard, active and Reserve forces. Finally, DoD works with other federal agencies (DHS, DHHS, DoE, EPA) to share its technical and operational expertise on CBRN hazards.

Below is a list of documents that provide more information on Homeland Defense/Civil Support.